Function dfs_dentry_unref

components/dfs/dfs_v2/src/dfs_dentry.c:164–219

* @brief Decrease reference count for a directory entry (dentry) and free if count reaches zero * * @param[in,out] dentry Pointer to the directory entry structure to be unreferenced * * @return struct dfs_dentry* The same dentry pointer if ref_count > 0, NULL if freed */

 * @return struct dfs_dentry* The same dentry pointer if ref_count > 0, NULL if freed
 */
struct dfs_dentry *dfs_dentry_unref(struct dfs_dentry *dentry)
{
    rt_err_t ret = RT_EOK;

    if (dentry)
    {
        ret = dfs_file_lock();
        if (ret == RT_EOK)
        {
            if (dentry->flags & DENTRY_IS_ALLOCED)
            {
                rt_atomic_sub(&(dentry->ref_count), 1);
            }

            if (rt_atomic_load(&(dentry->ref_count)) == 0)
            {
                DLOG(msg, "dentry", "dentry", DLOG_MSG, "free dentry, ref_count=0");
                if (dentry->flags & DENTRY_IS_ADDHASH)
                {
                    rt_list_remove(&dentry->hashlist);
                }

                /* release vnode */
                if (dentry->vnode)
                {
                    dfs_vnode_unref(dentry->vnode);
                }

                /* release mnt */
                DLOG(msg, "dentry", "mnt", DLOG_MSG, "dfs_mnt_unref(dentry->mnt)");
                if (dentry->mnt)
                {
                    dfs_mnt_unref(dentry->mnt);
                }

                dfs_file_unlock();

                LOG_I("free a dentry: %p", dentry);
                rt_free(dentry->pathname);
                rt_free(dentry);
                dentry = RT_NULL;
            }
            else
            {
                if (dentry->vnode)
                {
                    rt_atomic_sub(&(dentry->vnode->ref_count), 1);
                }
                dfs_file_unlock();
                DLOG(note, "dentry", "dentry ref_count=%d", rt_atomic_load(&(dentry->ref_count)));
            }
        }
    }

    return dentry;
}

/**